Traditional molten salt batteries typically utilize a tubular design. Accordingly, traditional approaches and apparatuses for fabricating cathodes have accommodated the cons mints associated with tubular batteries. For example, the traditional technique for forming cathodes in molten salt batteries is to place granules of a transition metal and an alkali metal halide in the batteries and to vacuum infiltrate the granules with a molten salt. This technique requires plumbing for the molten salt and can result in inexact amounts of the salt because the amount added cannot be precisely controlled. More recently, molten salt batteries have been constructed according to a planar design. Accordingly, the approaches and apparatuses for fabricating cathodes can be adapted to better accommodate batteries of any shape and their assembly. Furthermore, the approaches and apparatuses can be improved to provide better quality control over the composition of the cathodes.